Percutaneous fine-needle aspiration biopsy is a relatively simple invasive procedure with good patient acceptance, low morbidity, and almost negligible mortality. It provides a diagnosis of pulmonary, hilar, and mediastinal masses quickly and accurately, thus eliminating many laboratory tests, saving hospital days, and thereby saving time and money. Percutaneous fine-needle aspiration biopsy should be performed early in the investigation of many types of intrathoracic lesions.